Modulation of aroma in Gonggan cloudy juice by high-pressure homogenization

High-pressure homogenization (HPH) is a promising non-thermal technology for improving fruit juice quality, but its impact on the complex flavor of Gonggan cloudy juice remains unclear. This study investigated the effects of HPH using E-nose, gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry-mass spectrometry (GC-O-MS). While HPH did not alter basic physicochemical properties including total soluble solids (TSS), titratable acidity (TA) and reducing sugar content, it reduced vitamin C (Vc) content. At 400 and 600 bar, HPH significantly increased total phenol content by up to 23.1% and soluble pectin content by 94.26% via cell wall disruption. HPH simplified the aroma profile, increasing the terpene proportion to 85% while reducing aldehydes by over 85%, and the dominant aroma compound changed from linalool to (+)-limonene. GC-O-MS and ROAV analysis identified decanal, decanol, β-myrcene, and (+)-limonene as key markers and showed a reduction in key odorants (from 17 to 13-15). Treatment at 400 bar enhanced desirable citrus terpenoids, whereas 600 bar increased off-flavor compounds (e.g., D-carvone). Overall, HPH simplifies and intensifies the citrus character, with 400 bar identified as optimal for flavor enhancement, providing a scientific basis for targeted quality improvement in premium cloudy juices.